1. Field of the Invention
This invention pertains to a dye composition, an apparatus, and a method of using the same.
2. Description of the Prior Art and Objectives of the Invention
Many solvent and aqueous compositions and procedures for dyeing yarns, fabrics and other textile structures composed of polyesters, polyamides, polyacrylics and the like have been described over the years as evidenced by U.S. Pat. Nos. Re. 27,773; 3,467,474; 3,518,734; 3,530,214; 3,558,260; 3,770,528; 3,771,949; 3,943,105; 4,047,889; 4,055,971; and 4,115,054. Each of these procedures encompasses limitations however. Some are slow and inefficient; some require special pressure vessel equipment; some require volatile and possibly flammable solvents; some cause air or liquid pollution; some are hard to control sufficiently to assure consistent and uniform product quality; and some are expensive to operate.
One of the hardest fibers or fabric to dye is polyester, even though it is widely used in the industry. Experiments with high boiling point solvents, such as tri-ethylene glycol (TEG) acknowledged that this solvent is excellent for disperse and acid dyes. Removal or separation of the dye from the solvent is also accomplished without difficulty, and the elimination of any crocking tendency is straight forward and efficient. Problems arise however, because traces of TEG are left in the textile structure. These traces contain ether linkages which have a negative effect on light fastness. Likewise, experiments with "pure" dye in press cake form were also unsatisfactory.
Therefore, with the above considerations in mind it is an objective of the present invention to provide a dye composition which does not contain ether linkages.
It is a further objective of the present invention to provide a dye composition which suitably, uniformly dyes polymeric textile structures repeatedly over extended periods of time without the disadvantages of prior dyeing compositions and techniques.
It is yet a further objective of the present invention to provide a dyeing process which uses glycerin and a dye in its press cake form.
It is still a further objective to provide a method for dyeing which operates at a temperature above the melting point for specific dyes, but below their sublimation points.
It is an additional objective to provide a method for dyeing which works with dyes having multiple melting points.
It is another objective to provide a dye composition which contains 99.7% pure glycerin.
It is yet another objective to provide an apparatus which recycles the dye composition.
It is still another objective to provide a dyeing apparatus which directs the textile structure through a flowing dye composition where both the textile structure and the dye composition move at the same rate so as not to stress the textile structure.
It is a further objective to provide a dyeing apparatus which scours the textile structure before and after the textile structure is dyed.
It is still a further objective to provide a dyeing apparatus which recycles and repurifies the water used to scour the textile structure.
It yet a further objective to provide a method for dyeing a textile structure which incorporates elements of the dyeing apparatus and the dye composition.
It is another objective to provide a dyeing apparatus which operates between 160.degree. and 190.degree. C. for the first part of the dyeing step and then operates at a lower temperature for the remaining part of the dyeing step.
These and other objectives and advantages will become readily apparent to those skilled in the art upon reference to the following detailed description and drawings.